The coagulation of blood vessels is a necessary part of medical surgery and can be performed by an electrosurgical tool commonly known as an electrosurgical pencil or coagulator pencil. In this type of pencil, an electrically conductive metal tip either in the form of a blade or a needle extends outwardly from the forward end of the body of the pencil, the latter acting as a hand grip for a surgeon using the pencil. In use, the tissue of a patient is electrically connected to one side of an electrosurgical circuit, and the electrically conductive tip is connected to the other side of this circuit. When the metal tip touches or is near the tissue at the surgical site, a high frequency electrical current flows from the electrode to the tissue, thus coagulating and cauterizing the tissue. Use of the aforementioned electrosurgical pencil produces small plumes of smoke which should be removed from the site. This smoke is offensive because of its odor and it is potentially dangerous to medical personnel. Also evacuation of the smoke is very desirable so that the surgeon's view of the operation site remains relatively unobscured.
Recent U.S. Pat. No. 6,616,658 which issued to the present applicant describes an electrosurgical pencil of the aforementioned type. This known pencil has a main body portion forming a handle grippable by a user and having an electrode end and an exhaust end. This pencil comes with a metal electrode tip having a plastic base and removably mounted in the main body portion. There is an electrical switch in the form of a double-throw rocker switch mounted on a small circuit board that is in turn mounted within a passage formed in the main body. An elongate substantial unobstructed airflow vent is disposed within the body portion so as to extend from the electrode end to the exhaust end thereof.
More recent U.S. Pat. No. 7,537,594 to J. D. Sartor describes an electrosurgical suction coagulator that includes a handle and an elongate tube electrode or conductive suction tube extending from a front end of the handle. The suction tube has a closed distal end and an elongate slot disposed therealong for slidably receiving a needle electrode which is selectively extendable relative to the closed distal end to facilitate precise dissection. An aspiration port is disposed along a side of the suction tube for removing surgical fluids. In one version of this known coagulator the suction tube is slidingly and rotatably received within a channel formed in the handle of the device. A control rod is mechanically coupled to the suction tube and can be manipulated by the user to extend, retract and/or rotate the suction tube. The user can also manipulate the needle electrode via another control rod which operates in a similar manner.
The electrosurgical pencil described herein has both an elongate vent tube which can be readily adjusted in its longitudinal direction manually by the surgeon and also an elongate electrode tool which is adjustable independently in its longitudinal direction by manually pulling on a projecting forward section of the electrode tool.